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Homework Help: Lense/Image help (interactive diagram fun!)

  1. May 17, 2006 #1
    Hello, I have some questions dealing with an interactive diagram. to access the diagram go here: http://www.colorado.edu/physics/phet/simulations/lens/lens.swf
    when you go there set the radius of curvature to 1.0 m, the refractive index to 1.6, and the diameter to 1.2 m

    Ok first question:1. Calculate the focal length of the lens. So I know I need to use the lens maker's equation. 1/f = (n-1) (1/R1 - 1/R2)
    Plugging in numbers is the answer: .83 cm?

    2. Calculate the distance you need between the lens and the arrow so that its image is the same size as the object. What are your calculated values of p and q?
    What equation do I use to calculate this distance?


    Please help, muchas gracias.
     
  2. jcsd
  3. May 17, 2006 #2

    Doc Al

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    Staff: Mentor

    Your distance is in meters, so that's 0.83 m = 83 cm.

    Look up the thin lens equation.
     
  4. May 18, 2006 #3
    Ok the thin lens equation : 1/p + 1/q = 1/f
    f= 83 cm correct?
    So would that mean that p and q = 166cm ? Or is that the distance between the lens and the arrow ?
    please help
     
  5. May 18, 2006 #4

    Doc Al

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    Staff: Mentor

    Right.
    Right.
    Also right.
     
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